Grinding machine



.Z'NVeA/Toms a @um April 7, 1931.

H H. YERK ET AL GRINDING MACHINE Filed Aug. '7, 1924 7 Sheets-Sheet April 7, l931- H. H. Yl-:RK ET AL 1,799,491

GRINDING MACHINE Filed Aug. '7, 192.4 7 Sheets-Sheet 2 APY'il 7, A1931- H. H. YERK ET AL 1,799,491

GRINDING MACHINE '7 Sheetgrsheet 3 April 7, 1931. H. H. Y-ERK ET AL GHINDING MACHINE Filed Aug. 7, 1924 7 Sheets-She@t 4 Q .U Q w l vm i @M r| a 2 M .m ,ux 1; N w h e n@ a mm XN w `.n.o A m I r p M|| QN a I i u April 7, 1931- H. H. YERK ET AL 1,799,491

@BINDING MACHINE:l Filed Aug. '7,1924 '7 sheets-Sheet 5 I fia: ,5

y April 7, 1931@ H. H. YERK E'r AL 1,799,491

4GRINDING MACHINE Filed Aug. '7, 1924 7 Sheets-Sheet 6 EE. (a.

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H. H. YERK E-r AL 1,799,491

GRINDING MACHINE Filed Aug. 7, 1924 7 sheets-sheet 7 ffnung Inventum April 7, 1931.

.QON i .Puuh s? U w ma G M ...9 ..0 y.. QNH @QN om Mk .www 4 uw bm om .2: \l)/ r @v m @QN l .n2 l.. Hm E SN TM n- |U l mm E Q N2 L mi E mi Patented Apr. 7, 1931 UNITED STATES PATET 'ortie-E HENRY H. YERK .ANDy WILLIAM J'. BAMBERGECB, v0F DAVENPORT, IOWA, A SSIGITORSV TO MICRO MACHINE COMPANY, F BETT'ENDORF, IOWA, A CORPORATION OF IOWA calunnie MACHINE Application sied Aug-asi 7, i924.' serial nojrsaeac.

, This invention relates to grinding machines, and more particularly to internal grinders in which a grinding wheel is mounted on a spindle and caused to revolve bodily about a iiXed axis eccentric to its own and also to rotate upon its own axis while a suitable feed mechanism causes a relative movement longitudinally between the grinding wheel and the wor n f The present invention has for an obj ect the provision of driving means for causing both of the rotative movements of the spindle7 in a simple and efficient manner, and for so Vdriving the spindle that it will' have a uni` form, continuous, movement relative to the work with substantially no vibra-tion inV order that accurate grinding may be accomplishe'd and also that the surfaces ground may be smooth and have a superior finish.

A further object of the invention is to provide a driving means for causing the rotation of the spindle about its ownaxis, which drivingnieans will have a substantially uniform bodily movement corresponding kto that Y'of 2.5 the spindle7 so that back. lash and'other ir' regular movements of the spindle are substantially eliminated, thus permitting the grinding wheel to travel with a uniform mo-v tionrelative to thework and produce an eX- 130 cellent, ground surface. f

Another object cf the invention is to pro-v vide a mechanism for changing the rate of orbital movementl of the grinding wheel; spindle in relatively small increments or with intermerging gradations of speedr so ithat relatively small changes of speed can be ob.-V tained'to secure the best grinding ofcjylinders of various vdiameters or to secure grinding` of high quality Whenusingywheels 0f 40 different grain size,-thus making the machine of quite general application. Also, it is an ohject'of the invention to have the feeding mechanism so related to the change speed mechanism for the orbital movement of the spindle,v that when the speed of the latter is increased or decreased the feeding speed will be correspondingly increased or decreased.

A further object of the invention is to provide a common driving means deriving power frein a single source for causing the move *ure l.

ments of the grinding wheel spindle andV for causing the longitudinal feed ofthe Work, such driving means being eciently arranged to cause such movements with substantially no vibration and such means being easy to maintain and of a simple, efficient, and durable construction. i fr With the above and other objects in view the invention may be saidA lto comprise' the machine as illustrated in the accompanying drawings, yhereinafter described andpaltic ularly set vforth in the appended claims or suchvariations and modifica-tionsy thereof as will be obvious to those skilled in the art to which tlieinvention appertains. It isAthere-l foreto be understoodthat while the follow? 'but one of the various'inechanical -forms `in which the principle of the invention may be employed.

ving description and accompanying drawings' Reference should .be had to the accdnfip.anyJ

ing drawings forming a part of this specification in which Figure l is aV side elevation of al grinding machine embodying the invention.

Figure 2 is a side elevation of the machine from the side'fopposite that shown in Fig- Figure Sis an end elevation yof the 'mae chine showing the spindle driving' mechanism. Y Y Figure 4 is a horizontal section taken be.-

neath lthe bed and showing the driving connections from the main drivev shaft.

Figure 5 is an end viewjof th-e machiney with the spindle driving mechanism omitted.

Figure 6 is a vertical through the head.

Figure 7 is a fragmentary sectionon line longitudinal section v nl. f i i U D' 7 7 Figure l, showing the gearing `forfdriving the feeding mechanism. l

Figure 8 is a vertical vsection Aonflinez885 Figure 7. v y' A. Referring to the accompanying drawing,

the machine consists of a supporting vbase A which has at thetopthereofa bed'B upon;

which'thespindle carrying head C is, rigidly secured at one end." *A werk holder F is mounted upon the power driven table G for movement toward and from the spindle carrying head. The specific structure of the work holder does not concern the present invention, it being suflicient for the present disclosure that this work holder is adapted to be adjusted to rigidly support the cylinder to be ground in alinement with the axis about which the spindle is bodily rotated. The Work holder being mounted on the table Gr is moved longitudinally of the machine when the table G is moved by the usual raclr and pinion (not shown). The pinion is driven in the desired direction by suitable reversing gears in the casing E. The automatic reversal of the-table is controlled by adjustable stops 1 carried by a longitudinally extending bar 2 which is fixed to the table, the stop 1 engaging a control lever 3 projecting from the gear box 4. In addition to the power drive, the table may be operated by the hand wheel 4a as appears more fully hereinafter.

Referring particularly to Figure 6 of the drawing, the head (C) is provided with spaced bearing portions 5- in which the rotating spindle carrier 6 is journaled. The carrier 6 has an eccentric bore which has conical outwardly flaring end portions and which receives the spindle supporting member 7 which has an integral conical head 8 at its inner end and carries a conical sleeve 9 at its opposite end, the conical sleeve 9 being held in place by a nut 10 on the end of the member 7, the nut 10 being adjustable to engage the conical head 8 and the conical sleeve 9 in the flaring ends of the bore to prevent any endwise play between the supporting member 7 and the carrier 6.

The tool spindle 11 is journaled eccentrically in the inner sleeve support 7 and projects beyond the inner end of the head toward the work support and carries a suitn able tool suchas a grinding wheel 11a. The outer end of the spindle projects beyond the end of the frame and has a pulley 12 fixed thereto over which the belt which drives the spindle runs. The inner end of the spindle supporting sleeve 7 has a worm gear 13 fixed thereto which meshes with a worm 14 on a shaft 15 which may be operated manually b conventional means (not shown) to turn` t e sleeve 7 in the carrier 6. Since the sleeve 7 is eccentrically mounted in the carrier 6 and thespindle 11 Vis eccentrically mounted in the sleeve 7, the spindle may be adjusted with respect to the axis of the carrier 6 by rotating the sleeve 7 with respect to the carrier 6 by means of the worm 14. The spindle carrier 6-has two external gears 16 and 17 fixed thereto by which it may be rotated by power by means later described, or by hand y turning the handle 117, respectively, to revolve the spindle bodily during the operation of the machine. A suitable automatic feed device for adjusting the axis of the spindle relative to that of the spindle carrier 6 is preferably incorporated on this machine to vary the depth of cut of the grinding wheel while the machine is running. Such an yautomatic feed device is described in the application of H. M. Jerome, Serial No. 483,195, filed July 8, 1921.

The present invention relates particularly to the driving mechanism for the spindle, spindle carrier and feed mechanism above referred to and this driving mechanism will now be described. Mounted centrally upon the base of the machine at the end opposite that on which the head C is located is an electric motor 18 which has a shaft 19 which extends longitudinally of the base. Adjacent the motor there is a suitable clutch 2O by which the shaft 19 may be connected to or disconnected from a coaxial shaft 21, the clutch 2O being controlled by a shifter 22 which is operated by means of a suitable hand lever 23. The shaft 21 is ournaled adjacent its ends in fixed bearing standards 24 and 25, and from this shaft the spindle carrier and feed mechanisms are driven, as will be hereinafterV described.

The spindle is driven through mechanism carried at the end of the frame which is directly connected to the shaft 21. Upon the end of the base there is a' bracket frame D on which is mounted a horizontally slidable frame 26, which latter frame carries rollers 27 intermediate its ends and upper rollers 29 which engage, respectively, horizontal tracks 28, 30 on the member D. |The frame 26 is held in place from movement longitudinally of the machine by means of inner and outer rollers 31 and 32, respectively, carried by a bracket secured to the base of the machine and by similar rollers 34, 35 carried by a bracket on the frame D. The rollers 31 and 34 engage the outer face of the frame 26 and the rollers 32 and 35 engage the inner face thereof and thus hold the frame rigidly against movement longitudinally of the machine while permitting `it to freely move in a plane transverse to the machine.

Suspended from the spindle 11, immediately outside the horizontally movable frame 26, is a connecting arm 37 which is hung from the spindle 11 by a ball bearing 38 as shown in Figure 6. The arm 37 hangs vertically and is maintained at all times in vertical position by means of vertically disposed guides 39 and 40 adjacent the top and bottom of the frame 26 which are engaged by rollers 41 and 42, respectively, carried by the arm 37 adjacent the top and bottom thereof. Additional guides 43 preferably channel shaped, may be provided on the frame 26 to engage with rollers 43a on the arm'37 intermediate the upper and lower ends thereof.

ln order to counterbalance the weight of the frames 26 and 37 and the parts carried thereby, a counterweight may be provided. As will .be readily seen by reference to Figs. l and '4, the Iccunterweight l25`may act through a shaft 126.011 the lower .portion L27 of the-frame 26. 'The shaft 126 is shown as extending through the cross member 128 to form a Iball pivot :joint 129. It will be .seen that rby this means the spindle ll may be substantially relieved of the weight of the frame 26 and the varm 37 and parts `carried thereby. When the spindle is .ad-j usted as by turning housing 7 `relative to carrier 6 so 4that said spindle hasa ybodily movement `eccentric to its kown axis .due to the rotation `of carrier 6, the arm 37 follows -this bodily movement, the arm '37 being guided to move vertically and the frame 26 Vbeing guided to move horizontally so that all parts ofthe arm 37 move continuously and uniformly with the same bodi-r ly revolving movement that the spindle has. As the spindle is adjusted to vbe more `or less eccentric to the axis of the main cylinder, its bodily movement and the bodily movement of the arm 37 are, of course, increased or de`- creased. As shown :in Figure 6, the spindle is adjusted to have substantially its maximum eccentric vmovement but it, of course, may be adjusted by turning the spindle vhousing 7 so that it has very slight eccentric movement or none at all--that is so that its axis is in alinement with-the axis of the main cylinder.

rlhe arm 37 has a bearing portion 44 adj acent its lower end 1in which is journa'led a horizontal stub shaft which carries a relatively large belt pulley 46 outside the 'ari and projects inwardly through the frame 26 which is cut out to accommodate the spindle' n 1l and shaft 45. Abelt 47 runs ever the small spindle pulley l2 and large drive pulley 46 and the arm 37 carries an adjustable belt tightener-4'8 by means of which the belt may be held at the desired tension. The yshaft 45V is so disposed with respect to the axis of the shaft k2l that its bodily 4movement with respect to the axis thereof -corresponds substantially to the bodily movement of spindle l1 with respect to the axis of its carrier V6. The inner end of the shaft 45 is connected to the shaft 21 by means of telescopic shaft sections 49 and 50 connected to the shafts 2l and 45, respectively, "by universal joints 51 and 52.

It will thus be seen that the outer support 44 for the spindle drive has a bodily movement corresponding to the bodily movement of the spindle, and that such movement is ff uniform and continuous in one direction, so

that the tension of the belt 47 is always uniform and no vibration is transmittedgto the spindle, such as caused by the irregularswinging movement of therocker arms-now com# .monly used which move in arcsdifferent from that of the spindle and thus cause back lash and irregularfmovements of the belt. f

Preferably one of each pair of rolls for guiding the frame 26 and the arm 37 is mount'- `ed on an eccentric pin, as iswelfl understood in the art, vso that a relatively accurate lit may be made between .the rolls and the surfaces to be engaged thereby. Y y

In order to obtain the best lgrinding on cylinders rof various diameters or with grinding wheels of different grain size, it is necessary to provide means for Avarying the rates of bodily movement of the spindle and the longitudinalmovement ofthe work with respect -to the spindle.

` For example, it is well known that with a fine grain grinding wheel the bodily movement revolution or rotation of the grinding the orbitalrotation of the spindle over-a.

substantialfrange, so that on the same grindmachine the proper speeds may be ob-l tainedV for grinding cylinders of various` diameters and vfor grinding'withwheelsof small grain size and large grain size. changes of speed desirable formost eiicient operation may amount to several revolutions per vminute or they may be as small as one revolution per minute, depending upon ,the

variations in the work or the grinding wheel.

'Means `is therefore provided for varying the' orbital speed in small increments or with intermerging gradations in speed over a relativelywide range ofspeeds. y f

In addition to the necessity for making provision for the relatively small changes of speed of the bodily rotation of the spindle,- Vwe have found that it is very desirable to vvary the speed of the. work with respect to the spindle-and' this should bear va relation to the rate of bodily movement of the spindle, that is, when one is increased or decreased the other should correspondingly be increasedjor decreased.

It is, therefore, another object of the present invention to have the grinding wheel spindle and work table so driven that their speeds may be simultaneously and automatically varied in small increments or with intermerging gradations to obtain the speeds most suitable for a cylinder of any diam-` eter within the capacity of the machine or suitable for grinding wheels of any desired grain size, so that the proper speed for pro-l ducing the best groundsurfaces on any char acter of work m'ay be obtained. f l

A further advantage to be obtained by having suitable change speed mechanism for causing relatively small changes of speed The over a substantial range is that it is very desirable to have the orbital movement of the grinding wheel spindle a little slower when the grinding is clone wet than when the grinding is doneJ dry. Thus a grinding machine so equipped with a change speed meehanism is adapted to be used either as a dry or wet grinder and the correct speed for producing the best grinding can be obtained.

lVhile it is possible to incorporate in our machine separate means for changing the speed of the orbital movement of the spindle and travel of the work, this leaves the correct adjustment of such speeds to the operator and we have deemed it more desirable to have the travel of the work and the rate of orbital movement of the spindle so related that when the speed of one is increased or decreased the speed of the other is automatically increased or decreased in proper proportion.

In addition to having the work carrying table driven from the variable speed mechanism for driving the headstocl so that the rate of longitudinal travel of the table increases or decreases as the number of revolutions per minute of the headstock increases independent of the number of revolutions that are made per minute. This is in order that, as the depth of a cut is increased or decreased by varying the eccentricity of the spindle in the spindle carrier, the amount of longitudinal travel of the wheel relative to the work can be increased or decreased to vary the ratio between thev feed and spindle movements so that the best results in grinding may be obtained. i

The change speed device for' varying the orbital movement of the spindle and the longitudinal movement of the table will now be described. It is mounted upon therear side of the base below the head and consists of two reversely arranged cone pulleys 53 and 54 of the same size journaled in fired bearings one above the other with their axes and surfaces parallel and their peripherics slightly spaced.

The upper pulley 53 of these cone pulleys isdriven from the main drive shaft 21 in the following manner. It has at one end a. gear 55 which meshes with a gear 56 on a parallel stub shaft 57 which carries a belt pulley 58 over which runs a belt 59 which extends over a pulley 60 on the shaft 2l. |The lower cone pulley 54 is driven from the upper pulley by means of a belt 61 which encircles the lower cone pulley and is adjustable longitudinally of the pulleys to give the desired speed ratio between the two. As will loe explained, the spindle carrying sleeve and the work feed are both driven from the lower pulley 54 so that as the speed of one is varied the speed of the other is proportionately varied.

For shifting the belt 6l there is a yoke 62 straddling the belt and slidable along an inclined guide rod 63 parallel to the continuous peripheral portions of the conical surfaces of the cones. rlhe yoke l62 is connected to the ends of a cable 64 which runs over a pulley or sheave 65 adjacent one end of the cone pulleys and has its upper and lower runs parallel to the guide rod 63. Adjacent the forward end of the base, the cable 64 is guided transversely through the base over guide pulleys 66 and 6? onthe rear side of the base adjacent the cone pulleys there over, pulleys 68 adj acent the bottom of the base and pulleys 69 adjacent the top thereof beneath the head, and over horizontally disposed and horizontally alined pulleys 70 at the front of the base. The portion of the cable between the pulleys 70 is disposed horizontally and outside of the casing at the front of the machine and has attached thereto a handle 71 by which the cable may be shifted to shift the yoke 62 and belt 6l longitudinally of the cone pulleys. |lhe handle Z1 is provided with a pointer 72 and extending along the cable and above the same is a suitably graduated scale 72 along which the pointer moves. The scale Z3 provides means for indicating very accurately the speeds for which the spindle rotating and feed mechanism are set so that the operator may very quickly set the change speed mechanism to the proper point for the size of the work and the kind of grinding wheel used.

For operating the spindle carrying sleeve the shaft carrying the lower pulley 54has iiXed thereto at its forward end a belt pulley 74 from'which runs a belt 75 which passes over a pulley 76 on a countershaft 7'? beneath the head, the shaft T7 having a spur gear 78 meshing with the spur gear 16 on the spindle carrying sleeve 6.

For operating the table G the lower cone pulley 54 has its opposite end a pulley 7 9 over which runs a belt 8() which passes over a pulley 8l on a counter shaft S2 journaled in the standards 24 and 25 directly beneath the drive shaft 2l. The countershaft 82 carries a second belt pulley 83 which drives the belt 84 which extends into the pulley housing 84a at one end of the feed gear boX 4 and engages the pulley 85 to operate the gearing within the gear bof; 4 through which the pinion and rack or other work shifting device is operated.

Within the gear box 4 there is a reversing gear indicated generally at 85a of the usual bevel gear and intermediate clutch type which, drives in either direction a stub shaft V86 which extends into the Vcasing beneath-'the bed and has upon its inner end a bevel'gear 87 which meshes withv a bevelgear 88 on a countershaft 89 .which carries a spur gear 90 meshing witheai larger gear 91 on a counter-shaft 92 which has fixed thereto a series of gears 93 which are'of gradually decreasing size toward the `forward end of the shaft. These gears -93 mesh with' gears 94 loosely mounted on a parallel shaft 95, the gears 94 varying in size in reverseforder as is common in speedch ange` gearing.l rlll-he shaft 95 is hollow and slidable therein is a key rod 96 carrying a key 97 which extendsthrough aV slot in the shaft 95 and is adaptedto engage with any one of the gears 94 to key it to the shaft. Between each of the gears 94 there is a neutral'space provided by washers 98 in which the key may-be positioned so that the driveof the shaft may be discontinued by shifting the key in either direction out of' engagement with any one of the gears 94.

, The shaft 95 being thus driven by anyone of the gearsl 94 servesv to drive thefwork table Gin ythe following manner. It has fixed thereto at its rear end a pinion 99 which. meshes with a pinion 100 carried yby the horizontal'` shaft 101 which drives .through coupling 102 the worm gear 108. VThe worm gear 104 carried on the 'vertical shaftv 105 is driven on the worm gear 108 and the shaft 105 projects up to the bed of the machineand carries a pinion 105a which engages theV rack (not shown) for moving the work table ,G backward and forward. Vi

The rod 96 projectsforwardly beyond the end of the hollow'shaft 95 and this projecting end hasy a yrack portion 106 formedv by closely spaced, parallel, circumferential grooves, the rack portion 106 being engaged by a pinion 107 by means of which the rod 96 may be shifted longitudinally. .The pinion v 107 is fixed to asleeve' 108 loose on the transverse handwheel shaft 109 and this sleeve has attached .thereto outside `the -casing a handle 110 `by means of which it `may be turned to shift thel key rod- 96to-engage any Y desired gear 94 to .obtain the desired rate v.of feed of the table Gr-or to'disconnect thek shaft 95 to stop the movement of the table.: It will be noted'that by shifting the rod 96 with thekey97 in either direction from thelgears 94 the key will engage a neutral washery 98.

which will stop the movement of the table Gr.Vv The operation that has just been described relates to the meansfor driving the table G automatically at Vany de'sired speed: In order,however, to pro-vide for manualoperation of the table so that it vcan be set at any desired point,lthe hand wheel shaft109, which may be operated in veither direction by the hand 'wheel 4a mounted thereon, carries a bevel gear 111 fixed to its inner end and this gear meshes with. a vbevel gear' 112 on a counter-shaft 113` extending parallel to the shaft 95, the shaft 113L having a pinion meshing with a pinion 115' ixe'djtothe shaft 95'; x i

It will thus be vseen that the table G'may be set to any 'desired position by the hand wheel 4a a'n'dthat the'handle 110 may be;

` for` changing the ratio of speeds of thet'ab'le; Y travel and spindlemovements tosuit the grinding machine to obtain the best results with various conditions; Such change of the ratiovr of speed is' of courseindependent of the'relationship between the table travel and the bodily movement yof the spindle, wherein the latter increasesor decreasesv in speed f when thev former increases'v or decreasesL in`A speed. This vlatter relationshiparises from the arrangeme'ntl whereby the driving mech-'a'- ni'sm for causing the bodily movement `of the' previously spindle and the driving mechanism for eaus'- ing longitudinal movement-of theta-ble areV driven from the same cone pulley, and the'- rate of rotation of the cone pulley maybey varied within relatively small amounts vover a relatively wide range by' means ofthe belt shifting mechanism associa-ted with the cone pulley mechanism aspreviously explained.

yIt will thus' be -seen that we havev devel` oped a grinding-machine ofi general appli-A cation to grind cylinders of various sizes- 'andi cylinders either dry or wet,as" desi-red. By

havingfthese* factors which so'V vitally affect el.

the grinding variabley and within the vcon-v trol of the operator it is-possibleto produce practic'allyany desired finish on work of widelyv differing properties.

It will be noted that our grinding machinev tlf is adapted to grind cylinders eitherl by thev dry or the wet process as desired.A For wet with grinding wheels of various grain size'v o and various diameters-and for'grindingsuch grindingy aV suitable hollow spindle carrying f a `liquid conducting tubel and ai suitable baffle plate such as shown in the application of VVilliam J. Baumberger, Serialy No. "602,068, filed November 20,y 1922, may be used.vv As indi' cated in Figure 6 but not shown in the other liguresof the drawing a hose maybe pro'- 1- vided to supply liquid tothe liquid conducti fing'. tube'121 carried by the spindle 11. A bracket 122 supported on the arm 37. engages the rear end of the spindle and togetl'ier' with vthe nut 123 contains ythe liquid and directs it into the tube 121 which passesthrough the spindle as in the copending application above vreferred to.` -K v It isl to be understood that *while wehave i indicated how our grinding machine isadapted for introducing the vliquid forjwet grinduit 'ing as oney way, that we are by no means confined to using this particular manner of supplying the liquid for wet grinding. Our machine Ydisclosed herein may be` equally well used to obtain a superior grade of dry grinding or to obtain the still better finishes which it is known can be produced by wet grinding.

In the operation of the machine a cylinder to be ground is clamped to the work support F carried by the table G. It is set manually so that the axis of the cylinder is in alineinent with the axis of the orbital movement of the spindle and the table G is operated by thehandle 4a so that the cylinder is in proper position longitudinally of the spindle for feeding it backward and forward. The operating handle 7l of the speed regulator 570 is adjustable on the scale 7 3 to bring the pointer 72 to the position to cause the proper number of revolutions per minute of the spindle for the size and character of the work being operated upon and the character, of grinding wheel being used. The handle 110 is set to cause the table to travel the correct amount longitudinally for each revolution of the head stock, as is determined by the depth of cut to be made, the character of grinding wheel to be used and the character of the work.

Furthermore it is to be understood that the particular forms of apparatus shown and described, and the particular procedure set forth, are presented. for purposes of explanation and illustation and that various modiications of said apparatus and procedure can be made without departing from our inventionas defined in the appended claims.

Vhat we claim is :y p Y I l. In a grinding machine, a grinding wheel spindle, means for revolving said spindle bodily about an axis eccentric to its own, means for rotating said spindle about its own axis, a supporting member carried by the spindle and being free to move in response to the bodily movement of thespindle'and a rotatable driven element carried by the supporting member for causing the rotation of thespindle on its own axis and means for driving said element and for driving the spindle therefrom.

2. In a machine of the character described,

.3. In a grinding machine, a grinding wheel i spindle, a rotatable support for the spindle having an axis of rotation parallel to the axis of the spindle, means for rotating said spindle support to impart a bodily revolving movement to the spindle, supporting means carried by the spindle, guiding means mounted on the machine and so arranged as to permit said supporting means to freely move in the same path as that of the bodily movement of the spindle but holding said supporting means against rotation with the spindle, a drive shaft and means for driving the spindle from said drive shaft through said supporting means.

Ll-. In a grinding machine, a grinding wheel spindle, a rotatable sleeve for the spindle, having an axis of rotation parallel to the axis of the spindle, means for rotating said sleeve to impart a bodily revolving movement to the spindle, supporting means carried by the spindle, guiding means on the machine so arranged as to permit said supporting means to freely move in the same path as that of the bodily movement of the spindle, a drive shaft section carried by said supporting means, means connecting said section with said spindle for revolving the spindle about its own axis, a driving shaft journaled in said machine, and connecting shaft sections telescopically connected together and connected by universal joints with said drive shaft section and driving shaft.

5. The invention specified in claim 4f in which said supporting means is counterweighted.

6. In a machine of the character described, a frame. having a head, a sleeve rotatable therein, a spindle journaled eccentrically in the sleeve, means for rotating the sleeve, a supporting member suspended'from the spindle, said supporting member having a bearing in which the spindle is journaled, a guide member slidably ymounted on the head and having guides for said supporting member which permit a movement of the supporting member relative to said guide member in a direction at an angle to the direction of movement of the guide member with respect to the frame, and driving means for the spindle mounted on said supporting member.

7. In a grinding machine, a grinding wheel spindle, means for revolving said spindle bodily about an axis eccentric to its own, a supporting arm carried by the spindle, a laterally movable frame mounted in guides on said machine for horizontal movement,

guides on said frame for permitting vertical 9. In a grinding machine, a grinding wheel spindle, means for revolving the spindle machine and receiving a bodily motion corresponding to the bodily motion of the spindle e about the parallel axis, adriving vshaft journaled in the base of the machine, shaft sections carried by said supporting memberv and connected with said driving shaft so` that the outer endof said section can move with said supporting member and a belt means connecting said outer shaft section vwith said spindle to drive the same about its own axis. Y

10. In a grinding machine, a grinding wheel spindle, means for simultaneously rotating the spindle about its own axis and about an axis parallel thereto, supporting means suspended from 'the spindle and partaling of the bodily movement thereof and movably mounted therein, a guide frame, said frame being laterally movable in guides on the grinding machine and having means 'to-guide said supporting means, whereby said supporting means has uniform, continuous bodily movement corresponding to that of vthe spindle, and driving means carried by said supporting means for causing rotation of the spindle about its own axis.

l1. In a giinding machine, a base,`a grinding wheel spindle supported on the base, a

laterally movable frame supported on guides mounted on said base,a supporting member suspended from the spindle, mountedin the frame and guidedV for vertical movement in the said laterally movable frame, means, for rotating the spindle bodily about an axis parallel to its own, driving means for rotatf ing the spindle aboutits own axis,r said latter means being carried -by the supporting member.

12. In a machine of the character described, a tool spindle having a pulley thereon, means for rotating said spindle bodily Vaboutan axis eccentric to its own, a second pulley larger than the spindle pulley and arigid supporting member upon which the second pulley `is mounted, said supportingl member being si'ispendedy from the spindle, a belt passing over said pulleys, ka drive shaft on a fixed support, and a driving connection from said drive shaft to said `second pulley. l

13. In .a `machine of the character described, a tool spindle, means for rotating saidspindle bodily about an axis eccentric to its own, a rigid supporting arm carried by the spindle, a driving element carried by said arm for rotating the spindle about its own axis, a fixed drive shaft, and a driving connection from said drive shaft Vto said driving element.

14. In a machine ofy the character described, a tool spindle, means for rotating said spindle bodily about an axis, eccentric to its own, a rigid arm carried by the spindle, pulleys carried by the spindle and arm, respectively, a belt connectingithe pulleys, guides y for permitting said arm to partake ofthe same bodily movement as the spi'ndle,means onsaid arm lfor driving thel pulleys`,=and means carried by the arm for keeping thebelt passing over said pulleys tight, whereby said spindle `is caused to have a;continuou`s,uni

form movement' substantially free' from` vibration. i, Y .v r

15. In a machine ,ofy the character de.

scribed,- a tool spindle,.means for rotating said spindle bodily about an axis eccentric to its own, a pulley mountedon the spindle, a,y second pulley, a rigid farm maintaining said spindle and pulley in definite relation, means for guiding said second pulley in a ciri cular path corresponding to the path of movement of the spindle pulley, and means for driving said second pulley comprising a roe tatable drive shaft fixed against bodily movement, and a shaft section connected by universal-connections with saidsecond pulley and said drive shaft. v 1 x 16. In a grinding machine, a grinding wheel spindle, means for rotating said spindlel bodily about any axis eccentricto its own and means for rotating it about its own axis, supporting means suspended from the 'spindle movably mounted in a guide frame and partaking of the bodily movement of said spindle, said guide frame being laterally movable in guides on the grinding machine and having means to guide said supporting means, said frameand supporting means be.

ing movable in substantially parallel verti-y cal planes transversely of the spindle andV vheld against movement longitudinally of the spindle, driving means carried by the supporting means for causing rotation of the f 17. In a grinding machine, a grindingV wheel spindle, means for rotating said spindle bodily about anaxis eccentric to its own and means for rotating the spindle about itsown axis', a rigid, guided supporting armcarried by said spindle for bodily movement therewith, a shaft carried by said arm to drive said spindle about its own axis, driving connections between said shaft and said spindle, alixed drive shaft and a pair of telescopic shaft sections connected ,byv uniand said shaft carried by the arm.

, 18. In a grinding machine, a grinding wheel spindle, means for revolving saidA spindle .bodily `about an axis eccentric to its own, means for rotating said spindleabout its own axis, said revolving and rotating Vversal connections with said fixed drive shaft means deriving power from a common driv-` carried by the spindle so that it has the same bodily movement as the spindle.

19. In an internal grinding machine for grinding cylindrical bores, in combination,

a tool spindle, means for rotating said spindle orbitally about an axis eccentrie'to its own,ra power transmission member disposed 1n unallned relation to and remote from said tool spindle, and means :for driving said spindle about its own axis from said member, including a rotary member eccentric to the tool spindle and moving therewith in Van exactly corresponding orbit.

20. In an internal grinding machine for grinding cylindrical bores, in combination, a grinding wheel spindle having an orbital movement about an axis eccentric to its own, the radius of said orbital movement being changeable, a power transmission member spaced from said spindle in an unalined relation to and remote from said spindle, a gyratory driving connection from said source of power to said spindle to cause rotation of said spindle about its own axis, said driving connection having a continuous and uniform orbital movement exactly corresponding to the orbital movement of the spindle.

In testimony whereof, we hereunto aiix our signatures.

HENRY II. YERK.

WILLIAM J. BAUMBERGER. 

